Cabinet doors as employed in mobile homes and the like are conventionally constructed of wood frame members adjacent their edges to which veneer is glued to opposite faces thereof. The frame members, usually four in number, and most frequently disposed in 90.degree. relationship, are provided with mitered joints which, prior to applying the veneer, are stapled together with a staple bridging each joint at both sides of the frame members. The purpose of the staples is to hold the mitered joints in abutting relationship and the frame members in proper angular relationship during handling, storing, and passage through glue coating apparatus just prior to application of a veneer to each side and stacking in a glue press. Thereafter, the staples no longer serve any essential purpose, since the glued veneer on both faces of the frame members provides the structural bond therebetween. Edges of the doors, are often routed to form a detail such as cove, ogee, etc. to enhance appearance. It is essential, accordingly, that no staples be present in the path of the detail cutter. They are, accordingly, located closely adjacent the inside corners of the frame.
In the application of the staples, it is common practice to lay the frame members on a flat surface with the joints abutting and sequentially apply a staple across each joint with a hand-held power operated staple gun containing a magazine of staples. After these are applied, the frame is turned over and the operation repeated.
Disadvantages of this stapling process are that it is not only relatively slow, since the staples are sequentially applied by hand manipulation, but also subject to misalignment of the mitered joints. The process, accordingly, is subject to economies of manufacture and improvements in quality of the finished door.
Machines for clamping mitered joints together while fastenings are applied thereto have been proposed, such as exemplified by U.S. Pat. No. 2,482,872 to Rapport, where nails are driven across the mitered joints of picture frames from the outsides thereof. As previously referred to, no metal fastenings can be tolerated in such locations in cabinet doors with detailed edges. Thus, staples bridging the mitered joints near their inside corners have been the only commercially practical temporary fastener for the purpose required.